How do limiting factors influence wildlife population sizes over time? Objective • Students will be able to identify the four elements of good habitat that species need to survive (food, shelter, water, and space). • Students will understand how changes in suitable habitat influence wildlife populations. • Students engage safely, respectfully, and willingly in physical activity. Background • Western Arctic Caribou Herd Working Group website: www.westernarcticcaribou.org • Alaska Department of Fish & Game web site: www.adfg.alaska.gov/index.cfm?adfg=caribou.main (Click on “Range and Habitat” ta Duration: 30 Minutes.